Impact-resisting anti-lacerative window units

ABSTRACT

An impact-resisting anti-lacerative window glass unit of laminate of a sandwich structure is disclosed, which comprises two exterior plate-like member made of a transparent organic polymer (A) and a transparent organic polymer (B) or a transparent inorganic material, respectively, and multilayer structure intermediate films made of at least two kinds of polymers (C). The multilayer structure intermediate films are interposed between two exterior plate-like members. A method of fitting such an impact-resisting anti-lacerative laminate to a window frame or an automobile is also disclosed, which comprises removing a fitting portion of a hard coated transparent organic polymer (A) and the multilayer structure intermediate films through peeling while remaining at least one layer of a high breaking strength material layer as one of at least two kinds of the polymers (C) in the multilayer structure intermediate films on a person&#39;s side, and fitting the laminate to the window frame or an automobile body with an adhesive sealant by utilizing a thus exposed surface.

BACKGROUND OF THE INVENTION

(1) Field of the Invention:

The present invention relates to anti-lacerative window glass unitswhich have excellent impact resistance and prevent skins, etc. of humanheads from being damaged with broken pieces of a glass body of asandwich structure when an automobile collides with an object. Morespecifically, the present invention relates to anti-lacerative windowglass units which have excellent impact resistance and in whichintermediate films of a multilayer structure (hereinafter referred to as"multilayer structure intermediate films") composed of at least twokinds of different polymers are interposed between two exteriorplate-like members which are composed of different kinds of organicpolymers or the same kind of the organic polymer or between two exteriorplate-like members which are composed of an organic polymer and aninorganic material, respectively. When in use, it is necessary toarrange the exterior platelike member of the organic polymer material ona person's side ("Person's side" is used throughout the specificationand claims to mean an interior side of a window in a house, anautomobile, etc.). The invention also relates to a method of fittingsuch anti-lacerative window glass laminates to window frames, automobilebodies, etc.

(2) Related Art Statement:

Materials conventionally used as wind shield in automobiles have beenimproved in the chronological order from a tempered glass, a partiallytempered glass, a laminated safety glass to a anti-lacerative laminatedglass aiming at enhancing the safety. To the contrary, the number ofglasses necessary increases to two from one and an organic resin film isbonded to the glass on a vehicle interior side. Thus, disadvantageousfactors occur from the economical standpoint, for instance weightincrease and cost-up.

That is, anti-lacerative window glasses which have conventionally beenused as safety glass such as windshield glass units each comprise alaminated glass unit using two glass plates as a fundamental structure,and possess an exterior sheet composed of an organic polymer bonded to aperson's side of a fundamental structure. Since the laminated glassplates as the fundamental structure themselves essentially have impactresistance, such anti-lacerative window glass units may be called highsafety windshield glass. However, a problem remains unsolved thateconomically disadvantageous factors such as weight increase, cost-up,etc. should surely be solved.

That is, if the number of a glass plate in the glass laminate as thefundamental structure of the conventional anti-lacerative window glassunit is decreased to one to reduce the weight and cost of the windshieldglass, economically unmeasurable effects will be obtained.

However, since glass itself is a brittle material, a sufficientpenetrating resistance cannot be exhibited only by a countermeasure suchas a lining of an urethane base film, polyvinylbutyral/hard coatpolyester film or ethylene-vinylacetate copolymer/hard coat polyesterfilm. Thus, it is a present situation that safety glasses which can wellwithstand practical uses have not been obtained.

SUMMARY OF THE INVENTION

It is a first object of the present invention to improve the drawbackspossessed by the conventional window glasses such as windshield glasses,and to provide impact-resisting anti-lacerative window glass units whichare light in weight and have excellent economy.

It is another object of the present invention to provide a method offitting such impact-resisting anti-lacerative window glass units towindow frames, automobile bodies, or the like in order that they may notdrop off along the window frames when in collision, while maintainingthe same strength as the conventional laminated glasses.

The present inventors had repeatedly made strenuous studies to solve theabove-mentioned problems, and discovered that sufficient impactresistance could be obtained even by using a single glass plate whenmultilayer structure intermediate films composed of at least two kindsof different polymers are used instead of a polyvinyl butyral film or anethylene-vinyl acetate copolymer conventionally used for lining. As aresult, they have accomplished the present invention.

According to the first aspect of the present invention, there isprovided an impact-resisting anti-lacerative window glass unit of asandwich structure, which comprises two exterior plate-like memberscomposed of a transparent organic polymer (A) and another transparentpolymer (B) or a transparent inorganic material on the opposite sidethereof, and multilayer structure intermediate films composed of atleast two kinds of different polymers (C) interposed between the twoexterior plate-like members.

According to another aspect of the present invention, there is provideda method of fitting such impact-resisting anti-lacerative window glassunits by removing a fitting portion of the impact-resistinganti-lacerative window glass unit at a fitting portion on a person'sside such that at least one layer of a higher breaking strength materialin the multilayer structure intermediate films composed of polymershaving different breaking strengths, and then fitting the window glassunit to a window frame, an automobile body or the like with an adhesivesealant at a thus exposed surface.

These and other objects, features and advantages of the presentinvention will be well appreciated upon reading of the followingdescription of the invention when taken in conjunction with the attacheddrawings, with the understanding that some modifications, variations andchanges of the same could be made by the skilled person in the art towhich the invention pertains without departing from the spirit of theinvention or the scope of claims appended hereto.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the invention, reference is made to theattached drawings, wherein:

FIGS. 1 through 5 are sectional views of impact-resistinganti-lacerative window glass units or laminates of Examples 1 and 2 andComparative Examples 1 through 3, respectively;

FIG. 6 is a partially sectional view of other anti-lacerative laminateused by way of example according to the second aspect of the presentinvention;

FIGS. 7 through 9 are partially sectional views of the anti-lacerativelaminate (on one side only) illustrating the fitting method according tothe present invention; and

FIGS. 10 and 11 are partially sectional views (on one side only)illustrating fitting methods as comparison.

DETAILED DESCRIPTION OF THE INVENTION

In the following, the present invention will be explained in moredetail. First, the two exterior plate-like members will be explained.

As examples of the exterior plate-like member composed of thetransparent polymer (A) used on a person's side according to the presentinvention, mention may concretely be made of a polyacryl resin film, apolyvinyl chloride resin film, a polyethylene terephthalate resin film,a polyamide resin film, an aromatic polyamide resin film, a polyesterpolyether resin film, a polysulfone resin film, a polyimide resin film,etc. The resin films surface-treated with a silane base hard coat agentis preferable because of their excellent wear resistance. Among them,the hard coat-applied polyethylene terephthalate resin film is mostpreferable from the standpoint of transparency, surface smoothness,economy, etc.

The thickness of this exterior plate-like member is preferably not morethan 0.15 mm, and more preferably from 0.075 mm to 0.125 mm. That is, ifit exceeds 0.15 mm, the penetrating resistance can be enhanced and thethickness of the intermediate films can be made thinner, but, to thecontrary, unfavorably, possibility that a human head undergoes aconcussion of the brain in collision inevitably increases.

As examples of the exterior plate-like member of a transparent organicpolymer on the opposite side, mention may concretely be made of apolyacryl plate, polyvinyl chloride plate, etc. As examples of theexterior plate-like member composed of an inorganic material, mentionmay concretely be made of a glass plate, a tempered glass plate, apartially tempered glass plate, etc.

Various combinations of the opposite exterior plate-like members arepossible by appropriately selecting the exterior plate-like members,but, a combination of [a glass plate/a hard coated polyethyleneterephthalate film] may be recited as the most suitable combination ofthe two exterior plate-like members.

Next, the multilayer structure intermediate films will be explainedbelow.

The intermediate films are fundamentally constituted by alternativelylaminating at least two kinds of a transparent resin layer havingexcellent adhesion and a layer of a high breaking strength materialhaving no adhesion such that the transparent resin layers havingexcellent adhesion are located on outermost layer sides.

As a material of the transparent resin layer having excellent adhesion,mention may concretely be made of an ethylene-vinyl acetate copolymer(hereinafter referred to as EVA), ethylene-vinyl acetate-triallylisocyanurate terpolymer (hereinafter referred to as EVAT), a partiallysaponified product of EVA, polybutylbutyral, polyvinylformal,polyurethane, etc.

Among them, transparent films made of EVA and EVAT are most preferable.

Since the polyvinyl butyral resin has the property (blocking) that isfilms are adhered to each other during storage or transportation, it isnecessary to cool them for preventing the blocking. Further, atemperature at which impact resistance is fully exhibited is set nearordinary temperature (23° C.) and impact resistance extremely lowers ata temperature range other than the above. Thus, this resin is not sopreferable.

As a material for the intermediate layer having a high breaking strengthas the other element, mention may concreted be made ofpolyethylene-terephthalate (hereinafter referred to as PET), variouspolyamides, various aromatic polyamides, various polyester polyethers,various polysulfones, various polyimides, etc. Among them, a film madeof PET is preferable from the standpoint of the surface smoothness andeconomy. With respect to the thicknesses of the intermediate films, thethickness of the transparent resin film having excellent adhesion as oneof the elements is preferably from 0.03 mm to 0.5 mm. If it exceeds 0.5mm, intended weight reduction can not be attained. On the other hand, ifit is less than 0.03 mm, resistance is insufficient.

The thickness of the high breaking strength material layer is preferablyfrom 0.03 to 0.125 mm. The reason therefor is that if it exceeds 0.125mm, there is high possibility that a human head undergoes concussion ofthe brain in collision, while less than 0.03 mm is unfavorable, becauseimpact resistance is insufficient.

Some automobile windshield glasses are colored at their upper portionsto prevent drivers from being blinded with light. For this purpose, thehigh strength material film in the multilayer structure intermediatefilms may be preliminarily colored through printing, or alternatively atransparent resin material layer having adhesion may be preliminarilycolored as in the conventional laminated glasses.

If necessary, heat ray reflecting film, an electrically conductive film,a colored film, an ornamental film or the like may be formed on any oneof the multilayer structure intermediate films to cope with theblinding.

As mentioned in the above, the impact-resisting anti-lacerative windowglass units having high impact-resistance and excellent broken glasspiece scattering-preventing characteristic over a wide range oftemperatures can be obtained.

Preferred embodiments according to the present invention will beexplained by way of examples. As shown in the following, it was foundout through various studies that an alternatively arranged laminateconsisting of an EVA or EVAT film and a PET film, particularly such alaminate of a three layer structure is excellent as the multilayerstructure intermediate films and that a combination of a glass plate anda hard coat PET film is preferable as the exterior plate-like members.##STR1##

In the above embodiment, sufficient performances can be obtained bythree multilayer structure intermediate films. Of course, a goodperformances can also be obtained by four or more intermediate films,but they are disadvantageous from the economical standpoint of view.

The present invention will be explained in more detail with reference tothe following examples. They are merely given in illustration of theinvention, but should never be interpreted to limit the scope of theinvention.

First, matters concerning Examples and Comparative Examples will bedescribed below.

(1) Preparation of sheets of adhesive transparent resin materials:

Compositions shown in Table 1 were each mixed by a roll mill heated atabout 80° C., and two kinds of transparent resin compositions wereprepared.

Next, sheets of an adhesive transparent resin material were prepared ina given thickness by using each of the above compositions as a startingmaterial by means of a press heated at about 100° C.

                  TABLE 1                                                         ______________________________________                                        Compositions for adherent intermediate layers                                 Recipe               Symbol                                                   (parts by weight)    A       B                                                ______________________________________                                        EVA                  100.0   100.0                                            (manufactured by Toyo Soda                                                    Kogyo Kabushiki Kaisha,                                                       Trade name: Ultrasen 634)                                                     Dicumyl peroxide     1.0     1.0                                              γ-Methacryloxypropyl                                                                         0.3     0.3                                              trimethoxysilane                                                              Triallylisocyanurate --      5.0                                              ______________________________________                                    

(2) High strength material for intermediate film layers:

Among PET films, O-type polyester (hereinafter referred to as O-PET)manufactured by Teijin Kabushiki Kaisha was mainly used as the highbreaking strength material of the intermediate film layers.

(3) An exterior sheet on a person's side:

As the exterior sheet on the person's side, a PET film (manufactured byToray Kabushiki Kaisha, trade name: Toughtop) (hereinafter referred toas hard coat PET film) which was hard coated on one side at a thicknessof several microns in the state that the hard coated surface wasdirected outside.

(4) Preparation of safety glass laminates:

A multilayer structure intermediate films were prepared by using the EVAsheet and the PET film at the desired thicknesses, and interposedbetween a float glass plate preliminarily washed and dried and the hardcoated PET film. Then, a cover glass plate (2 mm thick) was placed onthe float glass plate, which were preliminarily pressure bonded at about90° C. for 15 minutes under vacuum in a preliminarily pressure bondingvacuum bag. Then, the preliminarily pressure bonded laminate wascompletely pressure bonded at 143° C. for 50 minutes under 15 atoms inan autoclave vessel.

After the sample was taken out from the autoclave, the cover glass platewas removed, thereby obtaining a safety glass laminate.

(5) Performance-evaluating methods (Ball-dropping test):

(a) With respect to the glass laminates in Examples and ComparativeExamples, ball-dropping tests were carried out according to JIS R-3212by using a steel ball of 2.26 kg. With respect to each kind of the glasslaminates, six samples were tested.

(b) The test was carried out by leaving each sample in a thermostatvessel at 25° C. for 4 hours or more.

(c) Tests were conducted by dropping the steel ball onto an insideexterior sheet from a specific height.

In FIGS. 1 through 5, reference numerals 1 through 11 denote thefollowing (Compositions A and B in parentheses correspond to A and B inTable 1, respectively).

1. 0.1 mm thick hard coat PET film (Toray, Toughtop)

2. 0.1 mm thick EVA sheet (Composition A)

3. 0.1 mm thick O-PET film (manufactured by Teijin Kabushiki Kaisha)

4. 0.2 mm thick EVA sheet (Composition A)

5. 3 mm thick float glass

6. 0.1 mm thick EVAT sheet (Composition B)

7. 0.2 mm thick EVAT sheet (Composition B)

8. 0.4 mm thick EVAT sheet (Composition B)

9. 0.2 mm thick O-PET film

10. 0.3 mm thick EVAT sheet (Composition B)

11. 0.4 mm thick polyvinyl butyral film

EXAMPLE 1

A glass laminate having a structure shown in FIG. 1 was prepared. Theresulting glass laminate had excellent transparency and was free fromoptical strain. None of six samples allowed penetration of the steelball in the ball-dropping test (height, 4 mm).

Further, although tests were carried out again while the height fromwhich the steel ball was dropped was raised to 6 m, the steel ball didnot penetrate the samples.

EXAMPLE 2

A glass laminate having a structure shown in FIG. 2 was prepared. Thisglass laminate had excellent transparency and was free from opticalstrain.

The samples were subjected to the ball-dropping test, but none of themallowed penetration of the steel ball therethrough when the ball wasdropped from both heights of 4 m and 6 m.

COMPARATIVE EXAMPLE 1

A glass laminate shown in FIG. 3 was prepared by using a single EVATsheet layer as the intermediate layer.

The thus obtained samples were subjected to the ball-dropping test froma height of 4 m, and all allowed the penetration of the ball.

COMPARATIVE EXAMPLE 2

A glass laminate shown in FIG. 4 (material for the inner side exteriorsheet: O-PET film) was prepared.

In the ball falling tests in which a steel ball was dropped from aheight of 4 m or 6 m, the steel ball did not penetrate the samples.

While a height (a bound height) at which the steel ball bounded backwhen being dropped was within about 30 cm in the case of Examples 1 and2, that in the case of Comparative Examples 2 exhibited as large a valueas about 1.0 m to 1.5 m.

From the above comparison, Comparative Example 2 had insufficient impactabsorbing property when a human body actually collides with thelaminate. Thus, it has a problem in safety as one of key points, and isconsidered to be rejected.

COMPARATIVE EXAMPLE 3

A glass laminate as shown in FIG. 5 was prepared by using anintermediate film of a polyvinyl butyral (manufactured by Du'Pont; tradename Butasite).

The samples were subjected to the ball-dropping test from a height of 4m, which revealed that the steel ball penetrated through all thesamples.

In addition, it was found that the samples underwent perpetualdeformation with sight-through strain in a hot blast blowing test at 80°C. by means of a drier or a pencile-pushing test from the side of a hardcoat surface of the PET film and their heat resistance and compressionresistance were poorer. No such deformation was recognized in thesamples of Examples 1 and 2.

According to the present invention, the following effects can beattained.

(1) As compared with the conventional anti-lacerative window glass unitsconstituted such that a glass laminate using two glass plates isemployed as a fundamental structure and a layer made of an organicpolymer material is bonded to an inner side (person's side), theimpact-resisting anti-lacerative windows glass units according to thepresent invention are extremely economically advantageous in that theweight is largely reduced and cost is largely lowered.

(2) Since the impact-resisting anti-lacerative window glass unitsaccording to the present invention have excellent impact resistance andan amount of broken glass pieces scattering at the time of breakage incollision is extremely small, they have extremely high safety.

(3) In addition, since the impact-resisting anti-lacerative window glassunits according to the present invention have excellent heat resistanceand compression resistance, an applicable range is expected to widen.

Now, the second aspect of the present invention will be explained below.

The second aspect of the present invention relates to a method offitting the anti-lacerative laminates to window frames or automobilebodies. As mentioned above, the anti-lacerative laminates areconstituted by interposing the multilayer structure intermediate filmscomposed of at least two kinds of polymers having different breakingstrengths between the exterior plate-like members made of thetransparent polymer and the transparent inorganic material. The secondaspect of the present invention is directed to a method of fitting theanti-lacerative window glass units of the first aspect of the inventionto the window frames, etc. That is, as compared with the conventionalglass laminates using two glass plates, according to the anti-lacerativewindow glass unit in the first aspect of the invention, the weight isextremely reduced because a single glass plate is used. When it is usedas a front glass, economical effect is extremely large due to saved fuelconsumption, etc.

However, inconvenience occurs when such a anti-lacerative window glassunit is to be attached to a window frame, an automobile body or thelike, because a single glass plate is used.

That is, in the recent conventional anti-lacerative safety glass units,a transparent film having excellent adhesion is laminated upon theperson's side of the glass unit using two glass plates. Therefore, whenthe anti-lacerative window glass unit is fitted to the window frame orthe automobile body, the adhesive film made of the transparent organicpolymer is peeled off at a fitting portion to expose the glass surfaceand is fitted to the window frame or the automobile body by utilizingthe thus exposed glass surface. For this reason, even if the glasslaminate is broken along the inside of the adhered portion in collision,the whole window glass will not remove and drop off due to theintermediate film interposed and bonding between the laminate glassplates.

On the other hand, according to the anti-lacerative window glass unitsdeveloped by the present inventors using a single glass plate, the hardcoat layer of the exterior plate-like member on the person's side hasexcellent wear resistance, smoothness transparency, etc. among theperformances, while on the other hand, there is possibility that thewindow glass unit cannot be fitted to the window frame or the automobilebody by a bonding technique because the hard coat layer has no adhesion.If the layer or layers on the person's side are peeled off at thefitting portion and the window glass unit is fitted to the window frameor the automobile body at the glass surface according to theconventional method, the glass plate may be broken along the inside ofthe window frame at the time of collision since only a single glassplate is located at the fitting portion. Consequently, the whole windowmay be removed therefrom. Thus, this fitting technique cannot be appliedto the anti-lacerative window glass units of this type.

As mentioned in the above, to improve the above fitting method is animportant task to practically use the anti-lacerative laminates.

The second aspect of the present invention relates to a novel method offitting the anti-lacerative laminates comprising two exterior plate-likemembers of an outermost layer of a hard coated transparent organicpolymer on the person's side and a transparent inorganic material on theopen air side, and a multilayer structure intermediate films made of atleast two kinds of polymers having different breaking strengths insertedtherebetween, and is characterized in that when the anti-lacerativelaminate is to be fitted to a window frame or an automobile body, thefitting portion of the laminate is peeled off on the person's side whileleaving at least one layer of the high breaking strength material andthe anti-lacerative laminate is fitted to the window frame or theautomobile body with an adhesive sealant by utilizing the thus exposedsurface.

As examples of the inorganic transparent materials used for the exteriorplate-like member on the open air side, mention may be made of glass,tempered glass and partially tempered glass.

With respect to the exterior plate-like member made of the transparentorganic polymer used on the person's side, the same materials recited inthe explanation of the first aspect of the present invention may beused. The transparent organic polymers surfacetreated with a silane basehard coat agent are preferable because of their excellent wearresistance. Among them, the hard coated polyethylene terephthalate resinfilm is most preferable from the standpoint of the transparency, surfacesmoothness, economy, etc.

The same as mentioned in the above are said with respect to thethickness of the above exterior platelike member.

Next, the multilayer structure intermediate films made of at least twokinds of polymers having different breaking strengths interposed betweenthe two exterior plate-like members will be explained. As examples ofthe polymer as the intermediate film used for enhancing adhesion betweenthe two exterior plate-like members, a transparent ethylene-vinylacetate copolymer, an ethylene-vinyl acetate-triallylisocyanurateterpolymer, a partially saponified product of an ethylene-vinyl acetatecopolymer, polyvinyl butyral, polyvinyl formal, polyurethane, etc.

As mentioned in the foregoing, since the polyvinyl butyral has ablocking property (polyvinyl butyl films adhere to each other duringstorage and transportation), it is necessary to prevent the adhesionthrough cooling. In addition, a temperature at which the impactresistance is exhibited to the maximum is set near ordinary temperature(23° C.) and the impact resistance is lowered at a temperature rangeother than the above. Thus, the polyvinyl-butyral resin is not sopreferable. To the contrary, transparent films of the ethylene-vinylacetate copolymer and the ethylene-vinyl acetatetriallyisocyanurateterpolymer are most preferable because of being free from suchdisadvantages.

As examples of the polymer having higher breaking strength, polyethyleneterephthalate, various polyamides, various aromatic polyamides, variouspolyester polyethers, various polysulfones, various polyimides, etc. maybe recited.

Among them, the polyethylene terephthalate is more preferable from thestandpoint of the surface smoothness, strength, and economy.

FIG. 6 shows a preferred embodiment of the anti-lacerative laminate usedin the present invention. In FIGS. 6-11, reference numerals denote thefollow materials and values in parentheses do their preferablethicknesses.

12:a float glass as a transparent inorganic material (an exteriorplate-like member on the open air side) (1.0 to 5.0 mm)

13,15:EVAT film as an intermediate film material having excellentadhesion (0.03 to 0.5 mm)

14:PET film as a high breaking strength material (0.01 to 0.3 mm)

16:PET film (an exterior plate-like member on a person's side) (0.05 to0.3 mm including the hard coat layer 17).

17:hard coat layer

The fitting method according to the present invention will be explainedwith reference to FIGS. 7 to 11.

As mentioned in the above, when the anti-lacerative laminate is to befitted to the window frame or the automobile body, the multilayerstructure intermediate films are removed at the fitting portion on theperson's side provided that at least one layer of the high breakingstrength material among the intermediate films is remained and thelaminate is then fitted to the window frame or the automobile body withan adhesive sealant by utilizing the thus exposed surface. Withreference to the anti-lacerative laminate shown in FIG. 6 by way ofexample, at least the film 2 having excellent adhesion and the film 3made of the high breaking strength material are left as a fittingportion, and the intended object of the present invention is attained bybonding the fitting portion to the automobile body.

As examples of film-removing ways, while up to the PET film layer 3 asthe high breaking strength material is retained, the other layers on theperson's side are removed (FIG. 9). Or, up to the layer 4 is retained(FIG. 8). Alternatively, up to the layer 5 is retained (FIG. 7).

As concrete peeling methods, in FIG. 7, the hard coat layer only isremoved at the fitting portion by means of a sand paper or a steel wool.In FIGS. 8 and 9, a knife is inserted into a peeling location to removenecessary layers through peeling.

The method of removing only the surface hard coat layer with the sandpaper or the steel wool as in FIG. 7 has no problem in terms of theperformances, but it is troublesome in working and a peeled portion issurely prevented from extending beyond a window frame portion from thestandpoint of appearance. Thus, such a method is not so preferable inpractice due to accompanying difficulties.

To the contrary, the method of peeling as illustrated in the FIGS. 8 and9 are extremely convenient and preferable. As a matter of course, when amasking tape (for instance, a cellophane tape) is inserted and bondedbetween the layers to be separated and the layer or layers to be peeledare peeled together with the masking tape, working efficiency isimproved and products having good appearance can be obtained. Thus, suchmethods are effective.

As the method of fitting the fitting portion-peeled laminate to a windowframe or an automobile body, any one of a bonding technique or amechanically fitting technique may be employed. In the bondingtechnique, a one liquid type or two liquid hardening type sealant suchas an epoxy base sealant, an urethane base sealant or a silicon basesealant, which is ordinarily employed for fitting front glasses toautomobile bodies, is used alone or together with an adhesive primer ora bonding primer. The mechanically fitting method is a technique used inordinary constructing or building.

In the following, the second aspect of the present invention will beexplained in more detail with reference to specific Examples.

(1) Performance evaluations:

With respect to the performance evaluations, the same methods as statedin connection with the first aspect of the present invention wereemployed.

(2) Test samples

Test samples were prepared by peeling fitting portions of laminatesconsisting of the following layers of FIG. 6 as shown in FIGS. 7 to 11.In FIG. 6 through 11.

12:3 mm thick float glass

13 and 15:0.1 mm thick EVAT film

14:0.1 mm thick O-PET film (O-type polyester film) manufactured byTeijin Kabushiki Kaisha

16 and 17:0.1 mm thick hard coat PET

EXAMPLES 3 TO 5 AND COMPARATIVE EXAMPLES 4 and 5

Test samples were prepared by peeling off a fitting portion over a widthof 15 mm at four sides of each of anti-lacerative laminates having asize of 305 mm×305 mm as constructed in FIG. 6. Each of the samples hada sight opening of 275 mm×275 mm, and was bonded to a ball drop testingtable at the peeled-off portion of 15 mm wide at the four sides by usingurethane base adhesive. A steel ball was dropped onto the center of thelaminate from a height of 6 m, and results were observed.

The results were shown in Table 2.

                  TABLE 2                                                         ______________________________________                                        Results in performance evaluations                                                     Peeled       FIG. 3                                                  No.      location     No.     Results                                         ______________________________________                                        Compar-  Between layers                                                                             6       Six test samples                                ative    12 and 13            all dropped leaving                             Example 4                                                                              glass surface        four sides of 15 mm                                      exposed              width.                                          Compar-  Between layers                                                                             5       Six test samples                                ative    13 and 14            all dropped leaving                             Example 5                     four sides of 15 mm                                                           width.                                          Example 3                                                                              Between layers                                                                             4       Six test samples                                         14 and 15            all remained at                                                               window frames, and                                                            had good penetra-                                                             ting resistance.                                Example 4                                                                              Between layers                                                                             3       Six test samples                                         15 and 16            all remained at                                                               window frames, and                                                            has good penetra-                                                             ting resistance.                                Example 5                                                                              Between layers                                                                             2       Six test samples                                         16 and 17            all remained at                                                               window frames, and                                                            had good pentetra-                                                            ting resistance.                                ______________________________________                                    

As seen from the results in Table 2, in the case of Examples 3 to 5 inwhich the PET layer 14 was retained in the fitting portion, the laminatedid not disassembled or drop form the fitting table in collision withthe steel ball, and penetrating resistance is sufficient. Thus, theysufficiently meet the required performances.

To the contrary, in the case of Comparative Examples 4 and 5 in which noPET layer 14 was retained, the laminate was broken and dropped off inthe collision with the steel ball while the fitting portion onlyremained at the fitting table. Thus, Comparative Examples 4 and 5 areinappropriate methods.

The following effects were obtained by the completion of the secondaspect of the present invention.

(1) As compared with the conventional anti-lacerative laminate using thelaminate glass as a base, it becomes possible to fit the single glasstype anti-lacerative laminate of lighter weight and higher safety toautomobile bodies or window frames.

(2) As a result, the latter anti-lacerative laminates can be practicallyused, and great effects such as improved safety and reduced fuelconsumption of automobiles can be attained.

What is claimed is:
 1. An impact-resisting anti-lacerative window unitof a sandwich structure comprising two exterior plate-like members madeof a transparent organic polymer (A) and a transparent organic polymer(B) or a glass plate, respectively, and multilayer structureintermediate films interposed between the exterior platelike members,wherein said films consist essentially of alternatively laminatedethylene-vinyl acetate and ethylene-vinyl acetate triallyl isocyanurateterpolymer layers having therebetween a layer of a high breakingstrength material selected from the group consisting of polyethyleneterephthalate, polyamides, aromatic polyamides, polyester polyethers,polysulfones and polyimides.
 2. An impact-resisting anti-lacerativewindow unit according to claim 1, wherein said intermediate layer havinghigh breaking strength is polyethylene terephthalate.
 3. Animpact-resisting anti-lacerative window unit according to claim 1,wherein the exterior plate-like member made of the transparent organicpolymer material (A) is a transparent film of polyethyleneterephthalate.
 4. An impact-resisting anti-lacerative window unitaccording to claim 1, wherein a surface of the exterior plate-likemember of the transparent organic polymer (A) is treated with a silanebase hard coat agent.